The use of gas compressors is known. When gas is compressed, heat is generated and the temperature of the gas being compressed is elevated. If the use of dryers is desired to remove moisture from the compressed gas, the temperature of the compressed gas must be reduced to an appropriate value before reaching the dryers.
One known way of reducing the temperature of a compressed gas is the use of an after cooler. After coolers can utilize air or water to facilitate cooling. In the case of an after cooler utilizing air, an arrangement for facilitating airflow over external surfaces of the after cooler must be provided. One common way of facilitating this airflow is the use of a fan.
It is known to arrange a fan to provide air flow for the compressor and also provide air flow for the after cooler. In the case of oilless scroll compressors, it is known to provide ducting so that the cooling air provided by the fan is first used to cool the compressor. Then, once the cooling air has cooled the compressor, the ducting conveys the now warmed cooling air over the after cooler. In this arrangement, the compressed gas can only be cooled to the temperature that the warmed cooling air has already reached during its usage as a compressor cooling medium. Although the arrangement of using the warmed cooling air is mechanically advantageous, there exists a performance limitation if it is desired for the compressed to be even cooler.
Additionally, if a cabinet is used for sound reduction, the temperature of the compressor cooling air is appreciably warmer as compared to a compressor system that is mounted in the open (e.g., without a sound reducing cabinet). Additionally, a compressor system that is mounted in the open is able to take advantage of useful cooling from general airflow around the compressor system, whereas the use of a sound reducing cabinet substantially reduces this type of cooling.